1. Field of the Disclosure
This application relates generally to improvements to a seat arrangement structure. More particularly the present disclosure relates to improvements relating to a towel bar or operating handle assembly, used for adjusting a seat in lateral or longitudinal direction, to keep the seat arrangement in a locked position during an event of an impact force.
2. Description of the Related Art
Vehicle seats are designed to offer comfort, and space to an occupant by allowing seat adjustments to a desired position. The adjustable vehicle seat allows an occupant to obtain a more comfortable seating position and to provide space behind, in front or on side of the vehicle seat to assist in entering and exiting the vehicle or storing objects.
Vehicle seats are typically mounted on a seat arrangement device. The seat arrangement device allows for relative movement of the seat with respect to the vehicle and other seats respectively. For instance the seat arrangement device provides for a seat to be moved away or moved toward other seats, moved in lateral (sideways) or longitudinal (forward and backward) direction of the vehicle.
The seat arrangement device assembly and seat mounting is often a complex process since it involves various components assembled in a particular order to enable seat movement in desired direction. One of the components of seat arrangement device includes a track arrangement fitted with a seat sliding device to achieve the desired lateral and longitudinal movement of the seats. The lateral movement involves moving a seat towards a side of a vehicle or moving the seat towards the other seat followed by locking the seat in a desired position. Further, to lock the seat in a desired position a locking or latch mechanism is provided.
A linear adjustable vehicle seat allows an occupant to obtain a more comfortable seating position and to provide additional space around the vehicle seat for ease of entering and exiting or storing objects. Further, latch mechanisms are generally known for locking the vehicle seat position at a plurality of locations. Seat latch mechanisms are generally known as pawl and positive engagement latch-type devices and mechanisms.
A part of the seat sliding device that assists in locking and unlocking the seat in a desired position is called a towel bar or operating handle assembly. Typically the towel bars employ a lever and rotation mechanism whose function is to place the locking mechanism in a locked or unlocked position. The towel bar operates when a vertical force is applied to the lever that leads to the rotation of a bar connected to the locking mechanism, thus placing the locking mechanism in the locked or unlocked position. The force may be applied by an operator or may be generated during a vehicle crash.
In an event of a vehicle impact, increased of G-forces (g) are generated due to sudden acceleration and deceleration of the vehicle. G-force (g) is a measure of acceleration or deceleration and is not a force. These G-forces can also cause the towel bar or the operating bar assembly to unlock the seat.
The problem of unintentional unlocking of an upper rail, on which a seat is installed, from the lower rail is addressed in U.S. Pat. No. 5,799,920. The patent discloses a two piece release lever formed of an operating handle and an actuating lever which swivel about a pivot point to lock and unlock the seat. The operating handle is supported by a connecting head having profiled slots and a tension spring. The release lever is configured such that during an unintentional operation, the operating handle is pushed backwards in the profiled slots of the connecting head against the spring tension and is blocked at the rear end of the profiled slot thus preventing the release lever to unlock the seat. When the unintentional actuation is removed the spring pushes the operating handle towards the front end of the profiled slot. In case of an intentional actuation the operating handle remains at the front end of the profiled slot and the release lever can be operated by vertically upward and downward forces.